A beverage maker comprising a water reservoir and a beverage extract holder is well-known. For example, the beverage maker may be a coffee maker which is adapted to make hot coffee on the basis of water and an amount of coffee extract in the form of ground coffee beans, and which comprises heating means for heating water that is present in the water reservoir. Furthermore, the coffee extract may be provided in a disposable filter, wherein it is appropriate to denote the beverage extract holder as filter holder. In general, when the coffee maker is operated for the purpose of making coffee, steps as described in the following are taken.
In the first place, a user of the coffee maker performs preparatory actions. In particular, the user fills a disposable filter with an appropriate amount of coffee extract and places the filter in the beverage extract holder. Also, the user takes care that the water reservoir of the coffee maker is filled with a sufficient amount of water.
In respect of the filter holder, it is noted that embodiments of a coffee maker exist in which the filter holder is removably arranged in the coffee maker, wherein it is furthermore possible that a portion of a housing which is adapted to receive and hold the filter holder is pivotably arranged. In such a case, the step of placing a filter filled with an amount of coffee in the filter holder is preceded by pivoting the housing portion as mentioned to a position in which the housing is opened, and in which the filter holder is freely accessible. In the process, the user may decide to remove the filter holder from the housing portion for the purpose of placing the filter in the filter holder, and subsequently put the filter holder back in place in the housing portion. In any case, when the coffee maker comprises a pivotably arranged housing portion as mentioned, and the assembly of the filter holder and the filter is in place in the housing portion, the user puts the filter holder and the filter in an operative position in the coffee maker by pivoting the housing portion to a position in which the housing is closed.
After the preparatory actions have been completed, the user activates the coffee maker, wherein the heating means are switched on and heat the water. The hot water drips from the outlet opening of the water reservoir and is received in the filter. It is noted that it is possible that the entire water reservoir is positioned above the filter holder, but that this is not necessary. For example, in alternative embodiments of a coffee maker, a major part of the water reservoir is positioned at a more or less equal level than the filter holder, and the water reservoir comprises an outlet tube, wherein only an end of the tube having the outlet opening is positioned above the filter holder.
The coffee is obtained as a result of an interaction between the hot water and the amount of coffee extract which is present in the filter. In particular, the water moves through the amount of coffee extract, under the influence of gravity, wherein it is possible that additionally a pressure is applied. The coffee exits the filter holder through the outlet opening of the filter holder.
In practice, when the coffee maker as described in the foregoing is used, various problems may occur. Among other things, these problems are related to the fact that the outlet opening of the water reservoir is a narrow opening which is apt to get clogged. In the first place, it is possible that the outlet opening of the water reservoir gets clogged with scale particles and/or other contaminating particles, so that it takes a relatively long time for an appropriate amount of water to flow from the water reservoir to the filter holder. Furthermore, as a result, the taste of the coffee is badly influenced. In the second place, the outlet opening of the filter holder may be clogged with dirt, or blocked by the filter in some way. When this happens, not only is it annoying to a user that it takes a long time for the coffee to come out of the coffee maker, or that this does not happen at all, but there is a considerable chance that the filter holder overflows as a consequence of a larger inflow of water in the filter holder than an outflow of beverage from the filter holder. Overflow of the filter holder may also occur in case of overdosing of the coffee in the filter, due to a relatively high flow resistance.